Nutrient levels

Riddler05 · Jan 15, 2015

Randy Holmes-Farley,

I was wondering if you can give a concise range for optimal nutrient levels in a mixed reef. I hear anything under 10ppm nitrate should be ok with most LPS but you need 1ppm for SPS but what about a mixed tank. Also, is it possible to pull phosphate down too low even if done slowly?

I'm running biopellets and I find that I can't make fine adjustments so my nitrate is ether undetectable or around 5-8ppm. My tank is mostly LPS with couple of montis (about 6), porities (2), green slimer and 2 other Acros. I have all the usual suspects for LPS and I have 3 BTA which are growing like crazy, but are staying put which is nice. And yes I have two soft corals, a toadstool and a Kenya tree.

Any advice or insights would be greatly appreciated.

Thanks
Corey

Randy Holmes-Farley · Jan 15, 2015

I expect you are probably better off in the 5-8 range for that tank than undetectable, but you can judge based on how the corals look. A few ppm is probably a good place to be.

It is possible to pull phosphate too low for any coral, but not likely with biopellets as the main export mechanism. Phosphate might even end up higher than you want. I'd aim for roughly about 0.03 ppm, but again, judge by the look of the tank.

Lack of sufficient control is one thing I don't like about biopellets. How are you making the adjustment between 5-8 ppm and undetectable?

Riddler05 · Jan 20, 2015

Randy,

Thanks for your response. I know this is not very scientific but I just started feeding my tank a lot heavier and my nitrates started rising. I also started to run more GFO to compensate for the higher phosphates which like you said, the biopellets are pretty much useless for (IMO). I tried to adjust my feeding to reduce my nitrates to the 2-4 range but it just seems to be all or nothing.

Most of my corals look happy (except the acros) however they are growing very slowly. For example I have had a candy cane coral for over a year now and it has grown from 2 heads to 5 and I have a duncan coral which has grown from 3 to 6 heads. I have only been in the hobby a year and a half and my husbandry skills are probably not good enough to keep acros because I started with a frag pack of 4 and one by one they are dying of slow tissue necroses :-(

For the time being I have stopped buying all but easy corals such as montipora, LPS, and some soft corals. I currently do weekly water changes of 10 gallons (on a 90 gallon tank) and dose 200 ml of kalk at night to keep up with calc and alk .